September 1, 2014

What to look for in Gas Furnaces

HVAC systems are available with different options that affect both heating and cooling.  The fan motor in the furnace pushes both heated and cooled air through the HVAC system so when you replace the furnace, you are dealing with more than just heating for the winter.  Let’s look at the main components of a furnace to help you decide what would be the best furnace for you.

Fan motor or blower:  This is what moves both heated and cooled air throughout your home.  Most existing home furnaces have single speed fans that turn on and off as needed.  In fact, most HVAC system manufacturers today still use furnaces that only run at one speed.  Trane offers several models of furnaces with true variable speed fans.  The fans start off at ½ speed for a minute, then speeds up to around ¾ speed for several minutes and then runs at maximum speed until the temperature selected has been reached.  For winter use, this reduces the “cold air” blast of air that you currently feel when the heater comes on.  For summer use, this helps the air conditioner lower the humidity in your home by removing moisture from the air in the first few minutes that it runs each time.  In both cases, it reduces the start up pressure shock to the homes duct work when the blower first turns on.  In summary, a variable speed fan or blower is best for any air conditioning and heating system.

Heat Exchanger: This is the part of the furnace that creates heat by burning natural gas or propane.  Heat exchangers are usually either steel or aluminized steel.  The metal expands and contracts with usage which can cause a problem (cracking) with those that are welded together.  Trane uses aluminized steel heat exchangers that are crimped together, which allows for the expanding and contracting without cracking (longer life).

Gas Valve:  This is the part that controls the amount of gas that flows into the heat exchanger.  Most furnaces use a single stage gas valve that runs at maximum all the time.  A 2 stage gas valve will allow the heat exchanger to run at ½ of normal when mild temperature changes are needed and at full flow when a lot of heat is needed.  The 2 stage gas valve will reduce the amount of gas burned in mild temperature changes and reduce your energy costs for heating.  Trane offers several models of furnaces with 2 stage gas valves.

Furnace Cabinet:  The cabinet holds all the heating and fan components within it.  Most manufacturers use painted steel with some type of insulation in it.  Trane uses a high quality, heavy steel cabinet with a uniform paint finish.  Trane’s furnaces are fully insulated and they use automotive grade gaskets around the doors and panels which reduces noise and keeps the conditioned air inside the furnace.

So what’s the best furnace for you?  It’s a quality built unit that is properly sized for your home with 2 stages of heating and a variable speed fan or blower.

Nothing beats a Trane.

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